To conveniently support an electrical wiring device, such as a switch or receptacle, an electrical lighting fixture, or simply a covered plate, an electrical box is mounted in an opening formed in a wall or ceiling and the electrical wiring device is fastened to the box by mounting screws. Conventional electrical boxes are stamped from metal, but more recently these boxes are made from nonmetallic materials, such as thermoplastic compositions. These more recent electrical boxes are secured within the opening via two pivotal arms wherein one arm is mounted on a corner of each of the top and bottom end walls of the box diagonally opposite from one another. The electrical wiring device is secured to the box by threading screws within bosses formed integrally with the box and which extend from the center of the top and bottom end wall edges of the box.
However, these pivotal arms and bosses present several problems when positioning the electrical box within the opening of a wall or ceiling. For example, due to the placement of the arms and bosses, i.e., at one corner and in the center of the top and bottom walls, the box rocks from side to side if it is placed within a rectangular opening. In order to eliminate this rocking action, an irregularly shaped opening must be cut in the mounting surface, which is difficult and time consuming.
Examples of prior electrical boxes are disclosed in the following U.S. Pat. Nos. 2,491,742 to Lein; 3,392,943 to Baxter; 3,848,764 to Salg; 3,963,204 to Liss; 4,580,689 to Slater; 4,605,816 to Jorgensen et al; 4,666,055 to Lewis; and 4,874,905 to Schnell et al.
Thus, a need in the electrical art exists to provide an improved electrical box which can be easily mounted in a rectangular opening of a wall or ceiling. This invention addresses this need in the art, along with other needs which will become apparent to those skilled in the art once given this disclosure.